I may have read the same book as you, Womble, but I also understand that crofts were sized so that the tenant crofter remained beholden to the landlord to provide labour at busy times.
Currently reading "The Lowland Clearances Scotland's Silent Revolution 1760-1830" by Peter Aitchison and Andrew Cassell. The same tactics were employed by landlors in the lowlands 40 years earlier. Leases of land were terminated, land enclosed, farms amalgamated and expanded so the landless, if they were lucky, were employed in mills build by the landlords and often housed in planned villages, which kept them availabble for employment on the land at harvest time.